Spark-gap device



A. (J. NASH.

SPARK GAP DEVICE.

APPLICATION FILED MAYII, 1920..

1,382, 113. Patented June 21, 1921.

T INSULRHON I OFFICE.

ALEXANDER Q. NASH, OF ST. LOUIS, MISSOURI.

SPARK-GAP DEVICE.

To all whom it may concern Be it known that I, ALEXANDER Q. NASH,

.a citizen of the United States, residing at In the previous patent granted to me the potential of the ignition current is increased or the production of a disruptive discharge by interposing a contact ball between two terminals, one of the terminals forming a seat for the ball and the other spaced from the ball a sufficient distance to provide a properly proportioned spark gap.

The present invention is an improvment over the previously patented construction in that two spaced terminals are mounted upon an insulating block. One of these terminals is in the form of a retainer for a freely movable contact ball, while the other terminal cooperates with the ball to form a spark gap and, at the same time prevents the ball from jumping out of the retainer but without restricting its free movement in the retainer.

The particular advantages of the present construction constituting this improvement reside in the cooperative functions of the spaced terminals and ball, whereby the said freely movable contact ball is confined within certain limits by its retainer and is maintained in the retainer by one of the terminals forming the spark gap with the ball.

In the drawings: I

Figure 1 is a side elevation, in central section, through a device constructed in accordanoe with the present invention.

Fig. 2 is a front elevation thereof.

Fig. 3 is a top plan view.

Fig. 4 is a top plan view of a blank for a modified form of the device.

Fig. 5 is a front elevation of the modified form, and

Fig. 6 is a top plan view of the modified bell retaining te minal.

Specification of Letters Patent.

Patented June 21, 1921.

Application filed May 17, 1920. Serial No. 881,903.

In detail:

The device, as herein shown in Figs. 1 to 3- inclusive, comprises an insulation block 1 upon which is mounted a ball retaining terminal in the form of a cup 2 carried by right angle bracket 3 held to the insulating block by the binding post screw 4 which passes through theinsulation block 1 and carries a washer 5 held by the nut 6, the wire 8 being retained on the binding screw post 4 between the nut 6 and another nut 7. The cup 2 may be secured to the bracket 3 by any suitable means such as soldering, welding, or the like, and holes 9 through the bottom of the cup and the bracket provide for egress of dust and the like.

If desirable, the .cup 2 and its attendant bracket 3 may be blanked and stamped in a single piece. 4 The cu 2 receives a contact ball 10 which is only 0 sufficient size to project above the side wall of the'cup and yet be freely movable in the interior thereof. This contact ball 10 is retained within the cup 2 by a terminal member 11 which projects out over the top in the manner shown and is spaced sufficiently from the ball to provide a properly proportioned spark gap without permitting the ball to'jump out of the cup.

The terminal member 11 carries a right angle extension 12 seating against the insulation block 1 and having the slot 13 through which the binding post screw 14 is passed, a washer 15 and nut 16 securely clamping the terminal member 11 in a properly adjusted position with respect to the ball 10, A similar nut 17 clamps the wire 18 between the nut 16 and said nut 17. By this arrangement the terminal member v11 may be. moved for the purpose of adjustment with respect to the ball 10 or for the purpose of removing and replacing the ball 10.

The disruptive discharge of current, whereby the potential of such current is increased takes place through the gap above mentioned, the gap being at all times properly ventilated by reason of its open construction.

In the modification shown in Figs. 4, 5 and 6 the parts are identical with those shown in Figs. 1, 2 and 3, with the exception of the ball retaining cup which, in this modification, is formed of a blank 19 having several arms 20 which are bent up at right angles to the body of the blank, as shown in Figs. 5 and 6, with the result that a cup avoiding the claims of-the patent.

, I claim 1. In a sparkgap device, spaced terminals,

one forming a walled inclosure for a contact ball freely movable therein, and the other terminal maintaining the ball against displacement' from said inclosure.

2. In a spark gap device, spaced terminals, one forming a supporting cup for a contact ball freely movable thereon, and the other terminal maintaining the ball against displacement from the ball supporting cup and the gap and permit removal and replacement of the ball.

3. In aspark gap device, spaced terminals, one forming a cup, a contact ball freely movable within said cup, andthe other terminal forming a cup cover plate to prevent displacement of the ball from the cup and to form a gap with the ball.

4. In aspark gag device, spaced terminals, one comprlsing a at central portion havin upturned arms, a contact ball freely retaine on said central portions by said arms and projecting .thereabove, and the other terminal providin a ball retainin means spaced from the bal to form a spari gap.

5. In a spark gap device, spaced terminals, one comprising a castellated ball receiving cup, a contact ball freely retained within said cup, and the other terminal spaced above said cup and ball to form a spark gap and retaining the ball within the cup. adjustable with respect to the cup to form I In testimony whereof I aflix my signature.

ALEXANDER Q. NASH. 

